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**PhilSiswick** · 21st May 2007, 11:55

Quote: (Originally Posted by Abbo)

Mr. Hanssing, these are all very fair points, but all points covered in Mod 1 - at least in principle. The devil seems to be in the execution. In the oxygen consumption poll on
http://www.rebreatherworld.com/gener...er-minute.html
plenty of trained ranks appear to be running consumption rates of 2 litres/ min, while some claim to be below 1. I would be willing to bet that they are all aware of the points you make and attempt to implement them. What do people who use less than 1 litre think they do differently?

I wonder whether the variation you see in the polls is a) the difference between what people actually breathe and what they use for planning (i.e. a difference in reporting, rather than usage) or b) simply down to physiological differences between people. Just as RMV varies across experienced OC divers, would not O2 consumption vary depending on similar factors?

You shouldn't give up trying to improve on gas consumption but, immediate mitigations could include a) bigger cylinders, b) more cylinders (i.e spares on the boat for later dives) or c) finding Rebreather divers to dive with. Any of these (or all three) would give you time to get your consumption down without being under pressure to do it. My experience from OC indicates that, the more pressure there is, the less likely you are to achieve optimal gas consumption....

Cheers,

Phil

21st May 2007, 11:55	#4 (permalink)
PhilSiswick WSKD 0001 Current Rebreather/s: Evolution Other Rebreather/s: Inspiration Vision Join Date: Apr 2006 Location: Oxford, UK Posts: 922	Re: Getting the most out of your O2 tank Quote: (Originally Posted by Abbo) Mr. Hanssing, these are all very fair points, but all points covered in Mod 1 - at least in principle. The devil seems to be in the execution. In the oxygen consumption poll on http://www.rebreatherworld.com/gener...er-minute.html plenty of trained ranks appear to be running consumption rates of 2 litres/ min, while some claim to be below 1. I would be willing to bet that they are all aware of the points you make and attempt to implement them. What do people who use less than 1 litre think they do differently? I wonder whether the variation you see in the polls is a) the difference between what people actually breathe and what they use for planning (i.e. a difference in reporting, rather than usage) or b) simply down to physiological differences between people. Just as RMV varies across experienced OC divers, would not O2 consumption vary depending on similar factors? You shouldn't give up trying to improve on gas consumption but, immediate mitigations could include a) bigger cylinders, b) more cylinders (i.e spares on the boat for later dives) or c) finding Rebreather divers to dive with. Any of these (or all three) would give you time to get your consumption down without being under pressure to do it. My experience from OC indicates that, the more pressure there is, the less likely you are to achieve optimal gas consumption.... Cheers, Phil __________________ Phil No comment on open circuit... it's an evolutionary dead end not really worth discussing here. Dave Sutton, 2007 I have always felt that the dive I am on is not nearly important as the dives I plan to be on the rest of my life. Tom Rose, 2007 www.hugsac.org.uk
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